I am not sure about the script but there is one freeware program that keeps track of activity done on your computer.
LastActivityView is the app name, designed by Nirsoft. This app keeps track of every application opened or the file saved. This app can be used to keep track of the file changes being saved. You can also find out who did those changes if you have setup multiple accounts on Windows. Do note that you can only run this app on Windows. So if you are running Linux operating system then you may need other solution.
Another Windows based solution is to use Event Viewer. This app keeps track of the errors and issues and the application opened. So this may not keep all the application log. You can use similar such apps for reading the file save and open apps.
If these two custom solutions don't help your case then you may need to design your own script.